HydroBASINS lev08 watershed · #1080015170
Bassin de Swartrivier
A watershed (drainage basin) is not a body of water — it is the land area where rainfall converges towards a single river that eventually reaches the sea (or an endorheic basin). Boundaries follow ridgelines.
Crosses 1 administrative regions : Overberg
Sub-basin area
788,5km²
Upstream area
788,6km²
Discharge
5,91m³/s
Mean elev.
291m
Administrative coverage
1 dept-equivalent regions (GADM L2)
- 788.2 km²100.0% of basin
13 intersecting protected areas
Cape Floral Region Protected Areas
IUCN Not ApplicableWorld Heritage Site (natural or mixed)
52.46 km² overlap
Hottentots-Holland Mountain Catchment Area
IUCN Not ReportedMountain Catchment Area
40.13 km² overlap
Klein Houwhoek Private Nature Reserve
IUCN Not ReportedNature Reserve
11.55 km² overlap
Witdraai Private Nature Reserve
IUCN Not ReportedNature Reserve
9.78 km² overlap
Ruvami Private Nature Reserve
IUCN Not ReportedNature Reserve
9.14 km² overlap
Caledon Nature Reserve
IUCN Not ReportedNature Reserve
2.59 km² overlap
De Rust Nature Reserve
IUCN Not ReportedNature Reserve
2.39 km² overlap
Diepklowe Private Nature Reserve
IUCN Not ReportedNature Reserve
2.18 km² overlap
Klein Ezeljagt Private Nature Reserve
IUCN Not ReportedNature Reserve
1.49 km² overlap
4 more protected areassorted by overlap area
Eagle Rock Private Nature Reserve
IUCN Not ReportedNature Reserve
1.47 km² overlap
Craigantlet Nature Reserve
IUCN Not ReportedNature Reserve
0.48 km² overlap
Wetland of International Importance (Ramsar Site)
0.20 km² overlap
Shaw's Pass Nature Reserve
IUCN Not ReportedNature Reserve
0.00 km² overlap
Computed live · GADM 4.1 × HydroBASINS lev08 × WDPA · cached after first hit.
Species present
3 799 distinct species · 102 807 observations
Source: GBIF Occurrence snapshot 2026-05-01.
Ecological tissue
Sample of 37 species (selected proportionally per kingdom among those with at least one documented interaction here) to keep the graph readable. Hover for details, click to explore the full ecosystem of a species.
ℹ️ The territory contains many more species than displayed and all their documented interactions: the graph is intentionally the structural skeleton (top-N species by composite local score, edges filtered by Serrano 2009 disparity filter α=0.2).
Indicateurs du tissu écologique
Tissu écologique de Bassin de Swartrivier : 29 espèces dont 2 patrimoniales (LR IUCN CR/EN/VU) reliées par 37 interactions GloBI sur 4 types (connectance 5.3%, filtre Serrano α=0.2). 9 bulles taxonomiques (cascade genre/famille GloBI, ≥3 espèces).
Comparaison sur la connectance du réseau local complet vs distribution nationale (toutes les communes françaises).
Hydroclimate (BasinATLAS lev08)
Mean T°
15,5°C
Annual rain
717mm
Moisture idx (CMI)
-0,38
Runoff
272mm/an
PET
1 171mm
AET
592mm
Mean slope
7,5°
Water table
562cm
Forest
22%
Crops
59%
Urban
1%
Protected
20%
HydroATLAS BasinATLAS v10 (Linke et al. 2019) · HydroBASINS lev08 (Lehner & Grill 2013)